Conventional network interface for multisite RF trunking system

• US 5,481,545 A
• Filed: 08/26/1991
• Issued: 01/02/1996
• Est. Priority Date: 08/26/1991
• Status: Expired due to Term

• Current Assignee: Pine Valley Investments, Inc. (L3Harris Technologies, Inc.)
• Original Assignee: Ericsson, Inc. (Telefonaktiebolaget LM Ericsson)
• Inventors: Maedjaja, Samuel, Hughes, Houston H. III
• Primary Examiner(s): Olms, Douglas W.
• Assistant Examiner(s): Patel, Ajit
• Application Number:
  US07/749,534
• Time in Patent Office: 1,590 Days
• Field of Search: 370/110.1, 370/110.3, 370/95.1, 370/95.3, 370/97, 370/75, 370/76, 340/825.44, 340/825.48, 455/15, 455/17, 455/53.1, 455/33.1, 455/33.2, 455/33.2, 455/33.4, 455/35.1, 455/36.1, 455/7
• US Class Current: 370/327
• CPC Class Codes: H04W 84/08 Trunked mobile radio systems

Abstract

A gateway between a non-trunked ("conventional") RF communication system and digitally trunked RD communication system maps between trunked group IDs and non-trunked subaudible signalling tone frequencies. An interface between the two systems thus forms a "super group" including both trunked and non-trunked radios that can automatically communicate together. The gateway permits a customer to continue to use non-trunked components, and to cost-effectively integrate such components into a state-of-the-art trunked radio communications system.

Claims

1. In a radio frequency (RF) communication system including (a) at least one digitally trunked RF repeater which transmits a selected one of plural digital ID codes over the air to identify an associated selected one of a plurality of digitally trunked RF transceivers, and (b) at least one tone-based RF repeater which transmits a selected one of plural predetermined signalling tones over the air to identify an associated selected one of a plurality of tone-controlled RF transceivers, a method for providing communications between said trunked RF transceivers and said tone-controlled RF transceivers including the steps of:

(a) establishing correspondence between said selected one of said plural digital ID values and said selected one of said plural predetermined signalling tones,

(b) transmitting said selected one digital ID value with said digitally trunked RF repeater to call said selected one of said plurality of digitally trunked RF transaceivers,

(c) transmitting said selected one predetermined signalling tone with said tone-based RF repeater to call said selected one of said plurality of tone-controlled RF transceivers, and

(d) establishing a communications path between said digitally trunked RF repeater and said tone-based RF repeater to allow communications between said called digitally trunked RF transceiver and said called tone-controlled RF transceiver,

2. A method as in claim 1 wherein said plural predetermined signalling tones are subaudible.

3. A method as in claim 1 wherein said plural predetermined signalling tones comprise CTCSS selective squelch tones which have the effect of opening the squelch of said tone-controlled RF transceivers.

14. A method as in claim 1 further including allowing said digitally trunked RF repeater to communicate digitally with said tone-based RF repeater over a multisite switch.

15. A method as in claim 1 further including retransmitting received RF signals with said tone-based RF communication repeater.

16. A method as in claim 1 further including retransmitting received RF signals with said digitally trunked RF repeater.

17. A method as in claim 1 further including concurrently receiving plural different conversations over a plurality of corresponding trunked RF communications channels with said digitally trunked RF communication repeater, and retransmitting a selected one of said plural different received conversations with said tone-based RF communication repeater.

18. A method as in claim 17 further including selecting a one of said plural different conversations to retransmit with said tone-based RF communication repeater in response to a received digital ID value.

4. A digitally trunked radio frequency (RF) communications system including at least one digitally trunked RF transmitting arrangement communicating digital signals to plural digital radio transceivers over at least one trunked RF communications channel, said system for integrating plural tone-based RF transceivers into said trunked RF communications system, said system including:

tone receiving/recognizing means for receiving and recognizing signalling tones transmitted by at least one of the plural tone-based RF transceivers;

at least one tone-based radio transmitter for transmitting, over the air in response to signalling tones received and recognized by said tone receiving/recognizing means, radio messages including signalling tones to call corresponding ones of the plural tone-based RF transceivers; and

a memory specifying correspondence between at least one of said received and recognized signalling tones and at least one digital transceiver ID identifying at least one of said plural digital radio transceivers;

wherein said digitally trunked RF transmitting arrangement is coupled to said memory, said digitally trunked RF transmitting arrangement for transmitting a digital channel assignment radio message specifying said digital transceiver ID corresponding to signalling tones received and recognized by said tone receiving/recognizing means over said trunked RF communications channel.

11. An interface arrangement as in claim 4 wherein said signalling tones are subaudible.

12. An interface arrangement as in claim 4 wherein said memory specifies whether said received signalling tones are valid.

13. An interface arrangement as in claim 4 wherein said memory specifies correspondence between a set of predetermined tone frequencies and a corresponding set of predetermined digitally-encoded transceiver IDs.

5. In a digitally trunked RF communications system including plural digitally trunked RF transmitting sites communicating digital signals to plural digital radio transceivers via at least one trunked RF channel, an interface arrangement for integrating a non-trunked RF base station into said digitally trunked RF communications system, said interface arrangement including:

digital messaging means for (a) receiving, from at least one of said plural digitally trunked RF transmitting sites, a digital trunked channel request message specifying a digital transceiver ID identifying one of said plural digital radio transceivers and for (b) transmitting a digital trunked channel assignment message specifying said digital transceiver ID over the air;

a memory specifying correspondence between said digital transceiver ID and at least one non-trunked identification signal; and

non-trunked identification signal generating means coupled to said messaging means and to said memory for providing a non-trunked identification signal corresponding to said received digital transceiver ID so as to establish correspondence between (a) said one of said plural digital radio transceivers identified by said channel assignment message, and (b) at least one no-trunked radio transceiver, and for causing said non-trunked RF base station to transmit said provided non-trunked identification signal to call said non-trunked radio transceiver in response to receipt of said digital trunked channel request message.

6. An interface arrangement as in claim 5 wherein said provided non-trunked identification signal comprises at least one subaudible signalling tone.

7. An interface arrangement as in claim 5 wherein said memory stores information representing a plurality of digital transmitter IDs identifying a corresponding plurality of different groups of digital radio transceivers, and a corresponding plurality of associated signalling tones identifying a corresponding plurality of different groups of non-trunked radio transceivers.

8. An interface arrangement as in claim 5 wherein said memory specifies a sequence of plural signalling tones corresponding to said received digital transceiver ID, and said non-trunked identification signal generating means generates said sequence of plural signalling tones.

9. An interface arrangement as in claim 5 wherein said memory specifies predetermined tone frequencies corresponding to said received digital transceiver ID, and said non-trunked identification signal generating means generates said at least one signalling tone based on said predetermined frequencies.

10. An interface arrangement as in claim 5 wherein said memory specifies correspondence between a set of predetermined tone frequencies and a corresponding set of predetermined transceiver digital identification codes.

19. A RF communications system for permitting a group of plural digitally controlled RF transceivers to communicate with a group of plural tone controlled RF transceivers, said system including:

a first RF repeater which (a) transmits a predetermined digital identification code over the air for receipt by said group of digitally controlled RF transceivers in order to cause said group of digitally controlled RF transceivers to operate temporarily on a trunked radio communications channel, (b) receives, over the air, said predetermined digital identification code and associated first communicated signals from said group of plural digitally controlled RF transceivers, and (c) applies said received predetermined digital identification code and associated first communicated signals to a communications link;

said communications link for routing signals between said first RF repeater and a second RF repeater;

said second RF repeater coupled to said communications link for (a) transmitting tone signalling and associated communicated signals to said group of plural tone controlled RF transceivers over the air, and (b) receiving, over the air, at least one predetermined digital identification tone and associated second communicated signals from said group of tone controlled RF transceivers; and

an interface arrangement, coupled between said first RF repeater and said second RF repeater via said communications link, for establishing a supergroup containing said group of plural digitally controlled RF transceivers and said group of plural tone-controlled RF transceivers by applying said predetermined digital identification code and said associated second communicated signals to said communications link in response to receipt of said predetermined identifying tone by said second RF repeater, and controlling said second RF repeater to transmit said predetermined identifying tone and said associated first communicated signals to said group of plural tone controlled RF transceivers in response to receipt by said first RF repeater of said predetermined identifying digital code applied to a multisite switch.

20. In a digitally trunked RF communications system, a method for permitting a first group of digitally trunked RF transceivers to communicate with a second group of tone controlled RF transceivers said method comprising the following steps:

(a) receiving, over the air via a radio message, a predetermined digital identification code from said first group of digitally trunked RF transceivers;

(b) applying said received predetermined digital identification code to a digital network;

(c) monitoring said digital network for appearance of said predetermined digital identification code; and

(d) calling a supergroup including said first group of digitally trunked RF transceivers and said second group of tone controlled RF transceivers by (i) transmitting an RF message containing said predetermined digital identification code over the air to control said first group of digitally trunked RF transceivers to begin operating temporarily on a predetermined trunked radio channel, (ii) transmitting a RF message over the air including a predetermined identifying tone to control said second group of tone controlled RF transceivers to begin actively receiving radio messages in response to monitored appearance of said predetermined digital identification code on said digital network, and (iii) transmitting common signals to said first group of digitally trunked RF transceivers and to said second group of tone controlled RF transceivers.

21. A method as in claim 20 further including:

(e) receiving, over the air via a RF message, said predetermined identifying tone from said second group of tone controlled RF transceivers;

(f) applying said predetermined digital identification code to said digital network in response to receipt of said predetermined identifying tone by said receiving step (e); and

(g) transmitting said predetermined digital identification code over the air to call said first group of digitally trunked RF transceivers in response to said predetermined digital identification code applied to said digital network by said step (f).

22. In a digitally trunked RF communications system, a method for permitting a first group digitally trunked RF transceivers operating on a first RF channel to communicate with a second group of tone controlled RF transceivers operating on a second RF channel, said method comprising the following steps:

(a) receiving, over the air via said second R/F channel, a predetermined identifying tone from said second group of tone controlled RF transceivers;

(b) applying a predetermined digital identification code to a digital network in response to receipt of said predetermined identifying tone by said receiving step (a);

(c) monitoring said digital network for appearance of said predetermined digital identification code; and

(d) (i) transmitting said predetermined identifying tone over the air to call said second group of tone controlled RF transceivers, (ii) transmitting said predetermined digital identification code over the air to call said first group of digitally trunked RF transceivers in response to appearance of said predetermined digital identification code on said digital network, and (iii) transmitting common signals to said first group of digitally trunked RF transceivers over said first channel and to said second group of tone controlled RF transceivers over said second channel.

23. A method of communicating over the air with first and second radio transceivers comprising the following steps:

(a) establishing a correspondence between a first radio transceiver and a second radio transceiver; and

(b) calling both said first radio transceiver and said second radio transceiver whenever a call is to be initiated to either of said first and second radio transceivers, including the steps of;

(1) transmitting trunking control signals to said first radio transceiver to cause said first radio transceiver to move to and begin operating on a trunked radio communications channel,

(2) transmitting receiver enabling signals to said second radio transceiver over a non-trunked radio communications channel to cause said second radio transceiver to begin actively receiving radio signals on said non-trunked radio communications channel, and

(3) transmitting common signals to said first radio transceiver over said trunked radio communications channel and to said second radio transceiver over said non-trunked radio communications channel.